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From: Keir Fraser <keir.fraser@eu.citrix.com>
To: Jan Beulich <jbeulich@novell.com>
Cc: xen-devel@lists.xensource.com
Subject: Re: long latency of domain shutdown
Date: Mon, 28 Apr 2008 15:42:09 +0100	[thread overview]
Message-ID: <C43BA0D1.1FFA9%keir.fraser@eu.citrix.com> (raw)
In-Reply-To: <4815FBB8.76E4.0078.0@novell.com>




On 28/4/08 15:30, "Jan Beulich" <jbeulich@novell.com> wrote:

> Okay, thanks - so I indeed missed the call to hypercall_preempt_check()
> in relinquish_memory(), which is the key indicator here.
> 
> However, that change deals exclusively with domain shutdown, but not
> with the more general page table pinning/unpinning operations, which I
> believe are (as described) vulnerable to mis-use by a malicious guest (I
> realize that well behaved guests would not normally present a heavily
> populated address space here, but it also cannot  be entirely excluded)
> - the upper bound to the number of operations on x86-64 is 512**4
> or 2**36 l1 table entries (ignoring the hypervisor hole which doesn't
> need processing).

True. It turns out to be good enough in practice though.

 -- Keir

  reply	other threads:[~2008-04-28 14:42 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-04-28 13:45 long latency of domain shutdown Jan Beulich
2008-04-28 13:59 ` Keir Fraser
2008-04-28 14:30   ` Jan Beulich
2008-04-28 14:42     ` Keir Fraser [this message]
2008-05-14 15:54       ` Jan Beulich
2008-05-14 16:05         ` Jan Beulich
2008-05-14 16:08         ` Keir Fraser
     [not found] <48189781.76E4.0078.0@novell.com>
     [not found] ` <C43E4040.2022A%keir.fraser@eu.citrix.com>
2008-05-08  9:58   ` Jan Beulich
2008-05-08 10:12     ` Keir Fraser
2008-05-08 10:39       ` Jan Beulich
2008-05-08 10:52         ` Keir Fraser
2008-05-08 11:13           ` Jan Beulich
2008-05-08 12:11             ` Keir Fraser
2008-05-08 12:33               ` Jan Beulich
2008-05-08 12:36                 ` Keir Fraser
2008-05-08 14:29                   ` Jan Beulich
2008-05-08 14:38                     ` Keir Fraser
2008-05-09 10:23               ` Jan Beulich
2008-05-09 10:29                 ` Keir Fraser

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